1. Technical Field
The present invention relates to non-imaging optics, and more particularly to the distribution of illumination light using fiber optics.
2. Background Art
There are many applications for which it desired (or required) to have redundant sources of light. For example, the backlight for an aircraft cockpit display may require two separate light sources. If one of these should fail, the other one would provide backup illumination. Of course this could be accomplished by means of a moving mechanism that moves the failed light source out of the way while the operational one is moved into position to replace it. However, moving mechanisms add complexity, expense, increased space requirements, and reliability concerns. In addition, it may be intolerable to have even the short period of display dead time that would be required to change light sources.
There is a long felt need for a compact light generation and light distribution system that delivers cool, low angular divergence light to a large number of remote sites, such as aircraft displays, with a high light flux transmission efficiency.
A light distribution system has been developed to distribute cool light from a central light generation enclosure to a plurality of remote locations. More specifically, the light distribution system distributes light from one or more light generation enclosures (LGE), where each LGE includes a high intensity discharge (HID) lamp. An LGE can be exceptionally compact in relation to the power of the enclosed lamp. This compactness derives from the small volume mirror enclosure of a lamp centered within the enclosure.
A system according to the present invention may include a collection array, an ultraviolet to red converter, a combination array and a distribution array. Each of these components may be based on the use of the solid core optical fiber conduits and non-imaging optical morphing elements. The light transmitted by these solid core optical fiber conduits feed a plurality of morphing optical elements that may be made of glass, plastic, or any other suitable light transmitting optical medium, which morphing elements collimate the light they propagate and project the light beams from the morphing elements into object space. The projected beams illuminate one or more targets or feed one or more optical devices such as, for example, luminares.
The light from the LGE propagates through the light distribution system with exceptionally high efficiency and projects from it with exceptionally low angular divergence. This high efficiency results from optical designs morphing optical elements, the efficiency of solid core plastic optical fiber conduits, and the accurate sizing and coupling methodology implemented at the interfaces between adjacent elements. In accordance with an aspect of the invention, the morphing optical elements that are fed by light from the optical fiber conduits are structured to obtain low angular divergence. Specifically, the morphing optical elements have small circular input port apertures and large exit port apertures, thereby forming a plurality of collimator elements that project light beams having low angular divergence. Compared with light beams having high angular divergence, the low angular divergence light beams are more easily shaped, concentrated, and/or otherwise controlled thereby minimizing wasted light.